The installation of the Cummins into my '68 Highboy required such a large 'hump' in the firewall that the heater box had to go. So now I'm stuck with the fresh air supply whole in the passenger side kick plate and I'm trying to figure out what to do with it. Can I use the same slide that is on the driver's side and install it over the whole? I looked online and didn't see that slide for sale anywhere - just the gasket.

Eventually I'm going to install a Vintage Air in where the heater box was. Does anyone have any idea if the original ducting that supplied the heater box with fresh air would be us use installing the Vintage Air?

Peter

 

My question is, why did you install a diesel over rebuilding the EF engine. Diesel is still to expensive these days.

 

YES!! the factory vent set up on the driver's side will fit just like it was made for the passigers side!!!

Steve

 

And I have the air vents available in good used condition with the 6 factory screws. Email anytime from my web site linked below and in the sponsors sidebar.

 

if i want fresh air i open my window. that duct that goes on the passenger side is an enemy imo. why would you want to heat cold air? or cool hot air? if everything is recirculating inside the cab thats what makes me comfortable. because if the outside air is 5 degrees and your heating that, it aint the same as heating maybe 60 degree air inside the cab. assuming u live up north... i did for awhile.

 

I know why you did the Cummins swap. I recently got one myself but it's still in the D250. Man those engines are awesome! Very easy to work on as well. I hope to one day put it into a 73 - 79 dent side.

Just wanted to give you some solidarity.
The CTD into a Ford truck = win!!!

 

Thanks for all the help. I'll email you Mike.

The Cummins is a great engine. I had a fairly built 390 in the HighBoy before and there is absolutely no comparison between the two. And having the 48RE behind it instead of a C6 makes a lot of difference too.

Peter

 

that is interesting i didnt know it would.

i also dont have a heater, but the PO did what Dave would like. he blocked off the pasage with a metal plate that he glued in place. if you decide that you dont want to put a driver side vent in let me know and i will take some pics for you.

but i might just have to check out the idea of putting in a driver side box.

 

I just replaced my factory AC box with an after market one - long story - and was going to block off the outside duct as well. I thought what the hay lets see if it fits... even the bolt holes fit. You do need to add / drill two holes for the front screws... which i have yet to do.

You really want to use heated outside air when it is cold outside cause it is drier than the inside air. Heating inside are will fog the windows on a cold day.

By the way the room under the dash is pritty tight for the aftermarket AC unit... but is can be done.

Steve

 

wierd. that would only happen to me when it rained. all other times was fine and the heater really kicks butt. with the stock duct setup theres only 2 positions on that thing with the boot. open = cold air going thru vents, and closed = cold air hitting the passengers foot. i remember i would have the fan off and be driving 50 mph and i can feel air coming out of the vents and i'm like damnit!